mitt romney headed to denver today. the republican presidential nominee will hold a rally there this evening as he prepares for wednesday's debate. >>> vp candidate paul ryan will prepare for his debate in virginia. the republican vp candidate will hold a debate. vice president joe biden is using chris van holland to stand in for ryan. the debate is scheduled on october the 8th in kentucky. >>> the supreme court justices will rule on several key cases, including whether race should be a factor in college admissions. today's court will also decide whether to curtail parts of the voter rights act of 1985. it requires the federal government to oversee any election rule changes in states with a history of voter discrimination. also on the docket, whether the defense of marriage act is constitutional. it states the federal government will only recognize traditional marriages. >> right now president obama is focused on winning re-election, but he's already focused on winning a key election should he win. cnbc's seema mody is